Light-emitting device

Abstract

A light-emitting device includes a base member including a first surface, and a first recess on the first surface, a light emitter on a bottom surface of the first recess, and a wavelength converter in the first recess. The wavelength converter covers the light emitter and is in contact with an inner side surface (21c) of the first recess. The wavelength converter includes a plurality of wavelength conversion particles. An aspect ratio obtained by dividing a depth of the first recess by a maximum width of the bottom surface is greater than 1. The wavelength converter includes, on a surface of the wavelength converter opposite to a surface of the wavelength converter facing the bottom surface, a second recess recessed in a depth direction of the first recess.

1 . A light-emitting device, comprising:
 a base member including a first surface, and a first recess on the first surface;   a light emitter on a bottom surface of the first recess; and   a wavelength converter in the first recess, the wavelength converter covering the light emitter and being in contact with an inner side surface of the first recess, the wavelength converter including a plurality of wavelength conversion particles,   wherein an aspect ratio obtained by dividing a depth of the first recess by a maximum width of the bottom surface is greater than 1, and   the wavelength converter includes, on a surface of the wavelength converter opposite to a surface of the wavelength converter facing the bottom surface, a second recess recessed in a depth direction of the first recess.   
     
     
         2 . The light-emitting device according to  claim 1 , wherein
 the depth of the first recess is greater than or equal to twice a maximum thickness of the wavelength converter in the depth direction.   
     
     
         3 . The light-emitting device according to  claim 2 , wherein
 the wavelength converter satisfies 0.3≤d/(t−d)≤1, where d is a depth of the second recess, and t is the maximum thickness.   
     
     
         4 . The light-emitting device according to  claim 3 , wherein
 the depth of the second recess is greater than or equal to 10 μm.   
     
     
         5 . The light-emitting device according to  claim 1 , further comprising:
 a light-transmissive member between the light emitter and the wavelength converter.   
     
     
         6 . The light-emitting device according to  claim 1 , wherein
 the wavelength converter has higher density of the plurality of wavelength conversion particles in a portion closer to the first surface than in a portion closer to the bottom surface.   
     
     
         7 . The light-emitting device according to  claim 1 , wherein
 the wavelength converter includes a plurality of wavelength converter layers stacked on one another in the depth direction, and   a density of the plurality of wavelength conversion particles is lower at a position more away from a boundary between adjacent wavelength converter layers of the plurality of wavelength converter layers in the depth direction.   
     
     
         8 . The light-emitting device according to  claim 1 , wherein
 the base member includes a first substrate including a second surface, and a second substrate on the second surface, and the second substrate includes a third surface facing the second surface, and a fourth surface opposite to the third surface,   the second substrate includes a through-hole extending through the second substrate from the third surface to the fourth surface, and the through-hole exposes a portion of the second surface, and   the first recess is defined by an inner surface of the through-hole and the portion of the second surface.   
     
     
         9 . The light-emitting device according to  claim 8 , wherein
 the second substrate is thicker than the first substrate.   
     
     
         10 . The light-emitting device according to  claim 8 , wherein the second substrate has a higher thermal conductivity than the first substrate.